Where the little River Enns joins the Danube, about twenty kilometres upstream of Linz, the Romans built their frontier. This was Lauriacum, headquarters of the Second Italic Legion, who were stationed here from the late second century to guard the northern edge of the empire, the province of Noricum, against the tribes beyond the river. Around the fortress grew a civilian town that at its height may have held many thousands of people, and later a bishop is said to have lived here. The modern town of Enns, which takes pride in being the oldest in Austria, grew up beside it, and the legionary camp lay under what is now a mix of fields, streets and suburbs.
You will not find standing walls in the middle of town, and the archaeology is mostly beneath your feet. A museum in the old town and a small archaeological park tell the story, with reconstructed fragments, tombstones and a reconstruction of a part of the camp. The medieval town square is beautiful, dominated by a tall town tower from the sixteenth century, and the pastel houses and arcades have a calm charm. Look for the Roman-era cemetery finds in the museum.
The riding around is easy and pleasant, with the Danube on one side and the Alpine foothills of Upper Austria on the other. Take the river road, the B3, toward Wallsee and Grein, passing orchards, castles and villages, with little traffic and gentle bends. Further south, toward Steyr and the Enns valley, the road climbs into forested hills and the bends get more interesting. Spring blossoms and golden autumn are best, and in summer weekend cyclists share the river paths and sometimes the road.
Enns is a town of about ten thousand people, so you will find fuel, bakeries, cafés and a decent selection of inns, and there is a motorway junction nearby, with a vignette required on the A1. Try a schnitzel or a freshly baked pretzel, or a slice of apple strudel. Mauthausen, the village across the Danube, holds a former concentration camp memorial, a solemn counterpart to the Roman story, and worth visiting with respect. Traffic can be heavy on the main roads at commute times, so plan to ride in the middle of the day.